Apparatus for carrying out repair, maintenance or testing of apparatus, components and the like in hot cells

ABSTRACT

An apparatus is disclosed for carrying out repair, maintenance or testing of apparatus, components and the like in hot cells, more particularly hot cells of reprocessing plants for spent nuclear fuels. The position of damage zones is detected and ascertained with the use of coordinates. Replacement parts and tools are moved into the maintenance and work position in dependence upon the coordinate data, and the repair of maintenance work is automatically carried out under computer control, with remote operation and remote monitoring. For carrying out the work, computer-controlled handling machines and manipulators are used which are adapted to travel in controllable manner in the hot cell. The monitoring and detecting, using coordinates, of damage zones and defects may be carried out with the use of cameras and/or leak detectors.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This application is a division of copending application Ser. No.421,716, filed Sept. 22, 1982, now U.S. Pat. No. 4,526,311. Theinvention relates to a method for carrying out repair or maintenance ortesting of apparatus, components and the like, in hot cells, such as inreprocessing plants for spent nuclear fuels, and to apparatus forcarrying out the method.

2. Description of the Prior Art

The repair, assembly, disassembly, servicing or maintenance ofapparatus, equipment and components or the treatment of components inrooms or chambers subjected to radioactive radiation, more particularlyso-called hot cells in reprocessing plants for spent nuclear fuels, hashitherto required a considerable outlay in running expenses. The hotcells have to be decontaminated first before persons can enter them tocarry out the necessary work, and extensive safety measures are neededwhich involve considerable expense.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a method forcarrying out repair, maintenance (including servicing) or testing ofapparatus, components and the like in hot cells, more particularly ofreprocessing plants for spent nuclear fuels, so as to makedecontamination work unnecessary. This allows maintenance to be carriedout more quickly, more simply and more safely. It is also an object ofthe present invention to provide an apparatus for carrying out themethod.

According to one aspect of the present invention there is provided amethod of carrying out repair, maintenance or testing of apparatus,components and the like in a hot cell using one or more handlingmachines, machine tools, general tools, replacement parts, workingmaterials and testing devices, provided for such a purpose in the hotcell. The apparatus, components and the like are monitored for damageand defects and the position of the damage or defects is detected andascertained with the use of co-ordinates. The appropriate handlingmachines, machine tools, general tools, replacement parts, workingmaterials and testing devices are selected and moved into a servicingand working position controlled by the ascertained co-ordinates.Thereafter the necessary repair or maintenance work can be carried outmanually or automatically with the use of remote operation and remotemonitoring, whereby defective parts may be removed and replaced orrepaired.

According to another aspect of the present invention there is providedapparatus for carrying out the method described above with apparatus,components and the like arranged in stands and holders in a hot cell. Atleast one central controllable manipulator is arranged in the hot celland is mounted so as to be capable of horizontal and vertical travel andalso of rotary or pivotal movement. This manipulator is arranged tocooperate with each of a plurality of further controllable sidemanipulators which are arranged to be capable of horizontal travel.These manipulators are vertically spaced from one another. Monitoringdevices are provided for ascertaining damage or defect zones, by meansof which the position coordinates of the damage or defect zones can beascertained and given to a computer which is situated outside the hotcell and which is connected by means of control lines to themanipulators.

Preferably, the central manipulator is arranged on a T-shaped supportvehicle. This vehicle substantially comprises a transverse supportmounted so as to be capable of travelling horizontally on wheelslaterally on opposite walls of the hot cell, and a vertical columncentral supporting the transverse support. The column is provided at thelower end with a wheel running on the floor or a floor rail of the hotcell. The support vehicle comprising at least one support arm foraccommodating the central manipulator.

Alternatively, the central manipulator is transportable on a lorry-likesupport vehicle which runs on rails fixed to the cell floor and whichhas a central column. This column is supported by a gantry-like frameand carries a support arm on which the central manipulator is mounted soas to be capable of being fixed before work.

In each case the support arm may be arranged on the column so as to becapable of moving vertically upwards and downwards and pivotally through360°. The column itself may be rotatable.

The present invention affords substantial technical and economicadvantages. The present method and apparatus for carrying out the methodallow safe working in the hot cell and improvement in the quality of thework results. A substantial saving in cost is achieved owing to theimproved availability and due to personnel and material savings.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to enable the invention to be more readily understood,reference will now be made to the accompanying drawings which illustratediagrammatically and by way of example an embodiment of apparatus forcarrying out the method of the present invention, and in which:

FIG. 1 is a side view of the apparatus,

FIG. 2 is a plan view of the apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings, there is shown apparatus in accordancewith the invention arranged in a hot cell 2 of a reprocessing plant, theapparatus comprising a T-shaped support vehicle 4 for a centralmanipulator 6. The support vehicle 4 comprises an upper transversesupport 8 which is adapted to run laterally, horizontally, in the sidewalls 10 and 12 of the hot cell on wheels 14 and 16. Centrally thetransverse support 8 is supported by a column 18 comprising at its lowerend a wheel 20 running on the floor or on a floor rail of the hot cell.A support arm 22 on which the manipulator 6 is arranged is mounted so asto be capable of travelling upwards and downwards on the column 18. Thecolumn 18 is rotatable about its longitudinal axis. Monitoring cameras24 are arranged on the support arm 22, which may also be arranged to berotatable on the column. A plurality of central manipulators may also beprovided.

The support vehicle 4 and the central manipulator 6 are controlled bymeans of control cables 25. Within the reach of the manipulator orhandling machine there is also arranged on the column 18 an equipmenttable 26 which carries tools, replacement parts and working materialsready for the central manipulator to take up.

Substantially parallel to the direction of travel of the support vehicle4 there are arranged at the two sides of the support vehicle 4, alongthe walls of the hot cell, stands 28 for the process apparatus (notshown) of the reprocessing plant. Between the stands 28 and the walls ofthe cell there are situated in a plurality of vertically spaced planeshorizontally disposed running rails 30 for horizontally mobilemanipulators 32 which are each arranged on a mobile carriage or areconstructed to be capable of travelling themselves. The manipulators 32and their carriages are controllable by means of their own controllines. Directly below the manipulators 32 or the running rails 30,conduits 34 are provided for the process apparatus. The processapparatus are connected to one another by further conduits insofar asthis is necessary.

Further cameras 38 are arranged on the transverse support 8 of thesupport vehicle 4.

A crane 40 with a travelling crab or trolley 42 is arranged above thetransverse support 8, and supports further cameras (not shown).

The cameras 24, 38 and those not shown serve for monitoring thepositioning of the apparatus to be dealt with and more particularly formonitoring the process apparatus and its conduitry.

The entire apparatus in the hot cell 2 is connected by control cables 46to a monitoring and control room 48, with control desk 50, screens 52and computers 54, which is situated outside of the cell.

The apparatus operates as follows, and by way of example it will beassumed that a conduit 56 in the right-hand upper level (see FIG. 1) hasbeen found to be defective, for example by means of leak detectors 55and/or one of the cameras. After ascertaining the position coordinatesof the defect zones and the feeding of such coordinates into thecomputer 54, a repair operation is carried out which is initiated at thecontrol desk 50 and proceeds in an automatically remote-controlledmanner, the central manipulator 6 having amongst other things the taskof removing the required tool and the required repair material from theequipment table 26 and bringing them to the defect zone. Using themanipulators 6 and 32 and the tools and repair materials which have beenbrought to the relevant zone, the following repair steps then proceed,automatically remote-controlled by means of the computer oralternatively in manually controlled manner: sawing-out of the defectiveconduit section, aligning of the two free conduit ends, clamping fast ofthe two aligned free conduit ends, aligning of the replacement conduitsection with the free conduit ends, weld seam preparation, andwelding-in of the replacement conduit section.

Even heavy objects can be transported and positioned in the hot cellwith the use of the crane 40.

In order to facilitate the monitoring of defects with the use ofcoordinates and the positioning of the parts and tools needed for repairwork, the stands 28 and conduits 34 and also the process apparatus arearranged in accordance with a specific pattern. The manipulators 6 and32 are so arranged that their working or effective ranges are adjacentone another or overlap one another.

I hereby claim:
 1. An apparatus for carrying out repair, maintenance or testing of components in a hot cell, comprising at least one central, controllable manipulator, a plurality of controllable side manipulators, a T-shaped support vehicle, an equipment table, a monitoring device and a control computer, said central manipulator being arranged in the hot cell and mounted so as to be capable of horizontal and vertical travel and also of rotary or pivotal movement, said central manipulator being arranged to cooperate with each of said side manipulators, said side manipulators being capable of horizontal travel, said side manipulators being arranged in a plurality of vertically spaced planes, said monitoring device being capable of ascertaining the position coordinates of damage or defect zones, said monitoring device being in communication with said computer such that said ascertained position coordinates can be fed into said computer, said computer being situated outside the hot cell and being connected by means of control lines to said central manipulator and said side manipulators, said central manipulator being mounted on said T-shaped support vehicle, said T-shaped support vehicle comprising a transverse support and a vertical column centrally supporting said transverse support, said transverse support being capable of horizontal travel with respect to a wall of the hot cell, said vertical column being capable of horizontal travel with respect to a floor of hot cell, said support vehicle additionally comprising at least one support arm on which said central manipulator is mounted, said equipment table being mounted on said vertical column of said support vehicle within reach of said central manipulator, said equipment table being designed to accommodate tools, replacement parts and materials required for carrying out repair and maintenance work in a position such that said tools, replacement parts and materials can be manipulated by said central manipulator.
 2. The apparatus of claim 1, wherein the support arm is capable of moving vertically and pivotably.
 3. The apparatus of claim 1, wherein the column is rotatable.
 4. The apparatus of claim 1, wherein the side manipulators are arranged on rails extending along opposite walls of the cell.
 5. The apparatus of claim 1, additionally comprising a horizontally mobile crane arranged above the support vehicle and provided with a travelling crab or trolley which can travel horizontally and transversely with respect to the direction of movement of the crane.
 6. The apparatus of claim 5, wherein the central manipulator, the support vehicle, the crane and the side manipulators are connected by supply and control lines to a computer and control desk situated outside the hot cell.
 7. The apparatus of claim 1, additionally comprising stands for accommodating said components contained in the hot cell, said stands being arranged between the central manipulator and the side manipulators.
 8. The apparatus of claim 1, wherein said monitoring device comprises leak detectors and cameras. 